Adding Avoidances to activity routing

This is my first garmin device and I could do with some help.
Does anybody know if you can add extra avoidances to route planning. When I ask my 5x to plan a route whilst walking, it likes to try and get me to follow a very busy road with no pavements. I can only find unpaved roads (which is off) and ferries (which is on) in the walking avoidance settings. Is there anyway to add main road etc..and make it follow footpaths instead. Thanks.